Researchers successfully enrol over 220 cases for landmark plague trial

May 8, 2024

The first randomised controlled trial powered to evaluate the efficacy and safety of treatments for bubonic plague has enrolled over 220 cases of confirmed or probable bubonic plague in Madagascar, marking a critical milestone in plague treatment research. 

Plague has afflicted humanity for millennia, and is still a high-risk pathogen today. However, current treatments are based on weak evidence, as no conclusive clinical trial has ever been conducted. Until today. The IMASOY trial in Madagascar has just successfully concluded enrolment with over 220 cases of confirmed or probable bubonic plague.

IMASOY is a randomised controlled clinical trial assessing a 10-day oral ciprofloxacin treatment compared to the first-line treatment in Madagascar, consisting of three days of an injectable aminoglycoside followed by seven days of oral ciprofloxacin. IMASOY is the first trial powered to evaluate efficacy and safety of treatments for bubonic plague and, while results are awaited, this enrolment milestone is still a significant step forward in the challenging journey to strengthen the evidence-base available to policy-makers. Detailed findings will be shared in Q4 2024.

Clinical trials of plague have traditionally been challenging due to the operational complexities of conducting a trial in plague-endemic regions and the lack of established trial methodologies. Achieving the planned sample size of this trial has been a monumental achievement made possible by the commitment of the institutions involved and the healthcare personnel of 82 peripheral health centres and hospitals in 13 districts in Madagascar.

IMASOY was conducted as a collaboration between the Institut Pasteur Madagascar (IPM), ISARIC, based in the Pandemic Sciences Institute at the University of Oxford (Sponsor), CHU Joseph Befelatanana, Centre d’Infectiologie Charles Mérieux (CICM), and London School of Hygiene & Tropical Medicine (LSHTM).

Detailed findings are expected at the end of 2024. This project is funded by Wellcome and UK International Development from the UK government.

Read more about the IMASOY trial.

Published by the Global Support Centre Communications Team

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